1. Field of the Invention
The present invention is related to a forming device for shaped decoration panels, and especially for shaped decoration panels made of non-ferrous alloy that are of high quality and have relieved fine decoration. The device is used to bend the shaped decoration panels.
2. Description of the Prior Art
Conventional high quality shaped decoration panels are made of gold, silver; copper, aluminum, titanium etc. Shaped decoration panels made of these materials satisfy the requirement of strength for durability and high quality, and are made generally by casting techniques. The techniques in the prior art do not consider the fact that the density of a cast article is not uniform for the entire surface. The surface is therefore difficult to grind and the resulting panel is not as strong as panels formed by other processes.
Shaped decoration panels made by a cold forming technique have the required strength and fineness of their surfaces. A cold forming technique producing a shaped decoration panel from a blank normally uses an alloy steel die. The die is formed having a die cavity with a desired shape, and the die can bear the pressure exerted by a forging press to forge the blank into the shaped decoration panel. The wall of the shaped decoration panel normally is formed to have relieved embossments (to be called decoration embossments hereinafter). The decoration embossments must be carved on the wall of the die cavity of the steel die in order to form a shape on the decoration panel; however, such a technique can only be used when forming a planar decoration panel. If the shaped decoration panel with relieved embossments is to be formed into an arciform decoration panel, this technique will not work.
To meet the strength requirement, the decorative portions on the shaped decoration panel should not be partially pressed before bending by a forming press. This may cause the shaped decoration panel to be weakened from stress. Bending a planar decoration panel in an arciform steel die cavity, as is the case in a conventional technique, tends to bend the decoration panel with non-uniform, concentrated stress. Due to stiffness of the die cavity, the relieves on the decoration panel which is arciform due to bending in the die cavity, tend to hold the die in the die cavity. This phenomenon causes scratching damage on the decoration embossments of the decoration panel when the panel is removed from the die cavity, and the product will therefore be inferior.
Due to this problem, manufacturers in the art mostly make the side walls of the decoration embossments of the decoration panel tapered in order to avoid die blocking, or difficulty in removing the panel from the die. However, tapering the walls reduces the delicacy as well as the scope of variation of modeling of the decoration embossments, which are desired to be artistic. Thus this solution is impractical.